Chapter 15: Solutions

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Chapter 15 Solutions

• Solutions, solutes solvents
• Water as a solvent, review of electrolytes
  nonelectrolytes
• Concentration Mass Percent Molarity
• Solution Preparation Dilution
• Stoichiometry of Reactions in Solution
• Aqueous Reactions
• Neutralization
• Concentration Normality

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Example 1

• How many moles of particles are
• produced when 1 mole of each of the
• following substances dissolves in
• water?
• KNO3 c. C2H3Br
• FeCl3 d. Na3PO4

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Example 2

• When 1.00 g of CaCl2 is dissolved in
• 100.0 g of water, what is the mass
• percent of CaCl2 in the resulting
• solution? What is the mass percent of
• Ca2 ions in the resulting solution?
• What is the mass percent of Cl- ions in
• the resulting solution?

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Example 3

• Explain how you would prepare 500.0 mL
• of 0.250 M AgNO3 from solid AgNO3 and
• water.
• Answer Weigh out 21.2 g of AgNO3, place it in
• a 500-mL volumetric flask, fill about half way
• and swirl to dissolve, then fill with water to
• calibration line.

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Example 4

• How many grams of table salt are present
• in 100.0 mL of a 0.500M solution?
• Answer 2.92 g NaCl

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Example 5

• Explain how you would prepare 2.00 L
• of 0.100M HCl from 12.0M HCl.
• Answer Measure out 16.7 mL of the
• 12.0M HCl and place it in a 2.00 L volumetric
• flask, then add water to the calibration line on
• the flask.

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Example 6

• Rust stains can be removed by washing a surface
• with a dilute solution of oxalic acid, H2C2O4. 
  The
• reaction is
• Fe2O3 (s)  6 H2C2O4 (aq) ? 2 Fe(C2O4)33-
  (aq)  3 H2O (l)   6 H (aq)
• What mass of rust, Fe2O3, can be removed by 1.0 L
  of
• a 0.14 M solution of oxalic acid?
• Answer 3.7 g of rust can be removed.

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Example 7

• If 25.0 mL of 0.200 M AgNO3 is mixed with 15.0
• mL of 0.500 M MgCl2, what mass of precipitate
• is formed? What is this precipitate?
• Answer 0.717 g of AgCl is formed

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Example 8

• A 50.00 mL sample of 1.677M H2SO4
• reacts with 1.993 M NaOH. What volume
• of the NaOH solution is required to
• neutralize the H2SO4?
• Answer 84.14 mL

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Example 9

• What is the equivalent mass of H3PO4?

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Example 10

• A solution is made by dissolving 1.15 g of
• Mg(OH)2 in enough water to produce
• 750.0 mL of solution. Calculate both the
• molarity and the normality of this
• solution.

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Example 11

• What volume of .50 N NaOH is needed to
• neutralize 15.0 mL of 0.35 N H2SO4?

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Example 12

• Suppose that 27.34 mL of standard
• 0.1021 M NaOH is required to neutralize
• 25.00 mL of an unknown H2SO4 solution.
• Calculate the molarity and the normality
• of the H2SO4 solution.